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STUDIES ON THE PRESSOR RESPONSES PRODUCED BY BRADYKININ AND KALLIDIN

1968; Wiley; Volume: 32; Issue: 2 Linguagem: Inglês

10.1111/j.1476-5381.1968.tb00976.x

2056-8177

W.J. Lang, Leonie Pearson,

Phytochemistry and Bioactive Compounds

The hypotensive effect of bradykinin was first described by Rocha e Silva, Beraldo & Rosenfeld (1949), and has been found in all mammals so far investigated (StUrmer & Cerletti, 1961; Schroder & Hempel, 1964).A number of studies, however, have shown that bradykinin may also increase the blood pressure, or cause a biphasic response.Thus, Croxatto, Belmar, Pereda & Labarca (1962) reported a hypertensive effect of bradykinin in rats with low blood pressure, and Lecomte, Troquet & Cession-Fossion (1964) described biphasic responses in rats and rabbits after repeated administration of bradykinin.Using cross-circulation techniques in dogs, it was shown by Benetato, Haulica, Muscalu, Bubuianu & Galesanu (1964) that intra-cranial administration of bradykinin produced a biphasic response.A rise in blood pressure has also been described when bradykinin is injected intra-arterially to various organs, including the brain, in cats and dogs.It was considered to be a reflex component of the "pseudo- affective" response to pain (Guzman, Braun & Lim, 1962).The related polypeptide kallidin resembles bradykinin in that it usually causes a fall in blood pressure (Stiirmer & Berde, 1963).It too, however, may have more complex effects.Thus, like bradykinin, it has a biphasic effect after repeated injections in rats or rabbits (Lecomte et al., 1964).Feldberg and Lewis (1964) have shown that bradykinin is a potent releaser of catechol- amines from the suprarenal medulla of cats; a similar action has been shown for both bradykinin and kallidin on the suprarenal medulla of dogs (Staszewska-Barczak & Vane, 1965).These peptides also stimulate the superior cervical ganglion of the cat (Lewis & Reit, 1965).Stimulation of the adrenal medulla, or ganglion-cells, or both, could explain the pressor effects of these polypeptides.The pressor phase of the cardiovascular response to bradykinin and kallidin in rabbits and rats is accentuated by guanethidine, pronethalol and desmethylimipramine (Miele, 1966 ; Lecomte et al., 1964), which suggests that it is caused by release of catecholamines from the adrenal medulla.We have frequently observed biphasic responses to bradykinin and kallidin in the course of experiments on their cardiovascular action in conscious and anaesthetized dogs (Pearson & Lang, 1967b).We also observed biphasic responses in other anaesthetized animals and chose the cat to analyse the mechanism of the pressure effects to these polypeptides more fully.A preliminary communication has been given on the findings reported in this paper (Pearson & Lang, 1967a).